C
- call data record (CDR)
- Information logged by the private branch
exchange (PBX) that tracks who made or received calls from whom,
the duration of the call, and other information. CDR is used to bill
back telecommunications charges to the appropriate parties.
- callback
- A process for invoking a method or a
desktop command, or for using the
gadget library in an application; the
means by which dialogs and gadgets respond to user input. For example,
when an administrator makes a selection with the mouse, some action is
initiated from the user interface to an underlying object representing
some system resource or component; that is, the user interface "calls
back" to the object to invoke some
method or series of methods.
- Carnegie-Mellon University (CMU)
- The source of a number of widely used computer programs.
- Carrier Sense Multiple Access/Collision
Detection (CSMA/CD)
- Multiple machines sharing a network and talking at the same time
cause collisions. When the collisions are detected, both machines stop
sending, wait a random amount of time, and then try to transmit again.
- CAS
- See Channel Associated Signalling (CAS).
- cascaded operation
- An operation in which the first object, originally acting as a
server for a client, now becomes a client of a second object on a
remote machine, and so on.
- CCITT
- See International Telecommunications Union
(ITU).
- CCMS
- See Change and Configuration Management Service
(CCMS).
- CCS
- See Common Channel Signalling (CCS).
- CDDI
- See Copper Distributed Data Interface (CDDI).
- CDE
- See Common Desktop Environment (CDE).
- CDR
- See call data record (CDR).
- cell
- A 53-byte chunk of data with embedded routing information. The first
five bytes are header and the last 48 bytes are the payload or data.
- cell loss priority (CLP)
- A two-bit field in the ATM
header that defines the priority of the cell,
for congestion avoidance and data loss routines.
- cell relay
- See Asynchronous Transfer Mode (ATM).
- central processing unit (CPU)
- That part of the computer that performs the actual processing; the
machine instruction executor. Also used to refer to the unit of the
computer that contains the CPU chip (such as the workstation base in a
NeXT slab); that part of the computer apart from the monitor and keyboard
and mouse.
- CERT
- See Computer Emergency Response team (CERT).
- CGI
- See Common Gateway Interface (CGI).
- Change and Configuration Management
Service (CCMS)
- Management by subscription. Allows applications to create abstract,
architecture- and platform-independent profiles that describe configuration
settings for the resources and services they manage.
- Channel Associated Signalling (CAS)
- Signalling bits are transmitted in-band, along with the digitized
voice itself.
- CICS
- See Customer Information Control System (CICS).
- CIDR
- See Classless Internet Domain Routing (CIDR).
- CIFS
- See Common Internet File System (CIFS).
- Classless Internet Domain Routing (CIDR)
- A protocol (defined in
RFC 1467) that allows for variable-length addresses that allows
for more- and less-specific routing information. This replaces the
old class A, class B, class C routing scheme.
- clean
- The file system is guaranteed
to have a static, stable structure. Only unmounted filesystems
or read-only file systems are clean by definition.
- CLEC
- See competitive local exchange carrier.
- CLI
- See command line interface (CLI).
- client
- The requestor of a service as provided by a
server. For example, a
"TME client" is a managed node;
xterm is an X Window System client.
- client/server model
- The structure by which services are implemented. A client process on
one host makes a request that a server process (which may or may not be
on another host) fulfills.
- client stub
- An ORB interface that provides for the
collection, transmission, marshaling and unmarshaling of data.
- clone
- Copy. A clone NetInfo server is an exact copy of a master NetInfo
server in the same subdomain. See domain (2),
NetInfo.
- CMU
- See Carnegie-Mellon University (CMU).
- CNAME record
- See DNS record types, CNAME record.
- collection
- A group of objects, with or without any particular relationships
other than belonging to a named group.
- collision
- When two interfaces on the same physical network transmit at the
same time, the packets interfere with each other. This collision causes
data loss so the interfaces have to retransmit the data.
- command line interface (CLI)
- A line-based (as opposed to a screen-based) interface between the
user and an application.
- Common Channel Signalling (CCS)
- Signalling bits are transmitted out-of-band, in a separate channel
from the digitized voice. Typically a number of voice channels have
their signalling combined together into a single signalling channel.
- Common Desktop Environment (CDE)
- A common windowing scheme, based on the X11 Motif system, used both
in Solaris and HP-UX, to provide a similar look and feel for users.
- Common Gateway Interface (CGI)
- A method to allow the user to interact with HTML documents; CGI allows
the use of forms and scripts on the World Wide Web (WWW). See also
HyperText Markup Language (HTML),
World Wide Web (WWW).
- Common Internet File System (CIFS)
- The name for Microsoft's version of a networked file system. See also Network File System (NFS), Windows NT File System (NTFS).
- Common Object Request Broker
Architecture (CORBA)
- An OMG and X/Open
specification introducing IDL,
ORB and BOA. The current
version is CORBA 1.1. CORBA was adopted by OMG from
a joint proposal by Digital Equipment Corporation, Hewlett-Packard Company,
HyperDesk Corporation, NCR Corporation, Object Design, Inc., and SunSoft,
Inc.
- competitive local exchange carrier (CLEC)
- A local telephone company that competes with an Incumbent Local Exchange Carrier (ILEC).
- Computer Emergency Response Team (CERT)
- The CERT Coordination Center is the organization that grew from the
computer emergency response team formed by the Defense
Advanced Research Projects Agency (DARPA) in November 1988 in response
to the needs identified during the Internet worm incident. The CERT charter
is to work with the Internet community to facilitate its response to computer
security events involving Internet hosts, to take proactive steps to raise
the community's awareness of computer security issues, and to conduct
research targeted at improving the security of existing systems.
- Computer-Telephony Integration (CTI)
- The integration of computers and telephone equipment; a computer
performing telephone services, such as placing calls or acting as an
answering machine.
- concatenated stripe
- Allows multiple disk partitions to be treated as a single large
partition by the kernel. See also Disk Suite.
- Copper Distributed Data Interface (CDDI)
- A high-speed networking standard whose underlying medium is copper
or telephone cable. The topology is dual-attached, counter-rotating
Token Ring. See also Fiber Distributed Data
Interface (FDDI).
- CORBA
- See Common Object Request Broker
Architecture (CORBA).
- CPE
- See customer premise equipment (CPE).
- CPU
- See central processing unit (CPU).
- cracker
- One who cracks, or breaks into, machines and/or networks. One who
breaks passwords. See also hacker.
- credentials package
- A cryptographically sealed data package containing information about
the principal, method, object, location, and authorization of a request.
- CSMA/CD
- See Carrier Sense Multiple Access/Collision Detection
(CSMA/CD).
- CTI
- See Computer-Telephony Integration (CTI).
- Customer Information Control System (CICS)
- The IBM architecture underlying the e-mail system, defining a
region or domain for electronic mail delivery.
- customer premise equipment (CPE)
- Telecommunications equipment located at a customer site (relative to
the telephone or telecommunications company).
- cylinder
- The same track from each platter of a disk. See also
platter.
- cylinder group
- A group of consecutive cylinders. See cylinder.